GE GEK-113045B Manual page 76

7.4 TROUBLESHOOTING
7.4 TROUBLESHOOTING
Table 7–1: SPM TROUBLESHOOTING (Sheet 1 of 2)
SYMPTOM POSSIBLE CAUSE
The SPM READY Control voltage missing.
message is not
displayed at
Connection plug is missing.
power-up (motor
not running).
Drawout cradle not fully
engaged
Wrong voltage is applied to the
V
Display is frozen.
Missing or improper motor-on,
motor-off input to SPM
SPM not properly programmed.
If the exciter voltage option is
supplied, exciter may not be
energized
Relay in tripped condition.
Internal connector cable loose.
Wiring to terminal points on
rear of unit are missing / loose.
7
Motor starts but Synchronizing slip set too low.
will not Motor cannot accelerate to slip
synchronize (FC level.
does not close)
FAR relay does not pick up
(SPM flashes FIELD IS APPLIED
but contactor does not close).
Field discharge resistor
(sometimes shipped
separately) is not connected or
incorrectly installed
Motor trying to accelerate
excessive load
A motor restart is aborted by
SCP operation (SQL CAGE TRIP
displayed)
Wiring to terminal points are
missing or loose.
7-
6
Courtesy of store.ips.us
and V terminals.
1 2
SPM Synchronous Motor Protection and Control
7 TESTING AND TROUBLESHOOTING
7.4.1 TROUBLESHOOTING GUIDE
CORRECTIVE ACTION
Check control fuses in synchronous controller (on primary and
secondary of control power secondary).
Insert connection plug at bottom of cradle assembly (see
Figure....)
Check removable cradle assembly and confirm that the top and
bottom rotating latches engage cradle and are positioned to
engage connection to disconnecting sockets at rear of case.
Control voltage must be in the range of 85 to 265 V AC.
Drop control power momentarily to the SPM and reapply. Some
portion of the display should be actively blinking. If not, the CPU is
not functioning. Replace with a new SPM.
Add or correct the isolated normally closed interlock from the main
contactor or relay operated with the main contactor. Interlock is to
be placed across MX to MX1 interlocks.
NOTE: This interlock must be open when the motor is engaged.
Call each program address and check setpoint data against the
desired setpoints (usually listed in the controller elementary).
Correct the operation of the DC field exciter so it outputs DC.
Press any keyboard button to RESET.
Remove front panel and check ribbon connectors for tightness.
Ensure connectors are not skewed or partially connected to pins.
Connect or tighten missing/loose wires to proper points on the
rear of the unit.
Refer to the setpoint programming instructions (Chapter 5) and
program a higher value of percent slip.
Check external FAR contact circuit wiring.
Check the connection of the field discharge resistor and correct if
necessary.
Unload or reduce load on motor shaft until FCX relay picks up.
The motor is taking too long to start or the stall time or run time
setpoint is set too low. Correct as necessary
Connect or tighten missing or loose wires to proper points on the
rear of the SPM.
GE Multilin